Fergie has got it right...they DOgang up on Ronaldo

Sir Alex Ferguson was right to identify Villarreal's tactic of 'systematic' foul tackles on Cristiano Ronaldo but what can a referee do about it if other teams adopt the same approach?

Italian official Roberto Rosetti did what he could to protect Ronaldo on Tuesday night, cautioning two Villarreal players and dismissing another for fouls on the United forward.

However, it is not the duty of the referee to single out 'skilful' or 'creative' players for special protection - rather, he should look out for team tactics to foul one opponent continually and clamp down on this.

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Red mist: Villarreal's Capdevila is sent off after fouling Ronaldo

Rosetti, who usually plies his trade in Serie A, will be no stranger to this 'team fouling' tactic on creative players.

Known as the machine-gun attack when applied by Antonio Rattin and his Argentina team-mates in the 1966 World Cup, it was proving successful for them until the the quarter-finals when they met England and, more especially, a strict referee in Germany's Rudolf Kreitlein.

So it is obviously not a new phenomenon and all top referees should be aware of the tactic and know how to deal with it.

They could learn from Rosetti's approach. His first caution, given to Javi Venta in the 27th minute, marked the third time that Ronaldo had been brought down with a heavy challenge.

Venta clearly indicated that it was his first offence but Rosetti rightly identified a team totting-up process and the yellow card was issued.

A second yellow was produced for the next foul on Ronaldo and, when this did not deter the home team, Rosetti upped the ante by showing a red card to Joan Capdevila, although this was not until the 83rd minute.

This was effective management of team fouling but Villarreal may still feel the tactic is worth repeating because Ronaldo was forced out of the game, no doubt nursing many bruises as well as the stud marks on his leg.